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Homework Help: Limit problem involving 1-sided limits

  1. Sep 15, 2012 #1
    1. The problem statement, all variables and given/known data
    [tex] \lim_{a→0+}\frac{1}{a}- \lim_{b→0-}\frac{1}{b} [/tex]

    2. Relevant equations

    3. The attempt at a solution
    I assume I would have to use the Cauchy definition of a limit to solve this, but I was wondering if there were any alternative ways.

  2. jcsd
  3. Sep 16, 2012 #2
    You cannot solve this at all, because neither of the two limits exist. Thus you cannot carry out the substraction.
  4. Sep 17, 2012 #3
    hmm personally I would say the first term gives +infinity and the second term gives - infinite; so subtracting the two would give +infinity. why is this wrong?
  5. Sep 17, 2012 #4
    Damn, I guess you're right ;-)
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